The present disclosure relates generally to the manufacturing of semiconductor devices, and in some embodiments, to a photolithography process.
Since the inception of the semiconductor industry, photolithography has been used for forming the components of integrated circuits. In operation, light beams pass through a mask, which has been patterned with a magnified image of the relevant integrated circuits. The light beams are then focused by a projection lens onto a wafer, resulting in an image of the integrated circuits in the photoresist, which performs the critical function of precise pattern formation.
However, a number of factors, such as solvent residues and undesirable liquid, may adversely affect the performance of the photolithography process, and especially the performance of the photoresist. In one example, solvent residues in photoresist may adversely contaminate the projection lens, especially in the case of wet lithography.
In a second example, following the deposition of a top anti-reflective coating (TARC) layer, the wafer is baked to reduce the solvent residues in the TARC. However, the additional baking process may undesirably alter the process window of the photoresist.
In a third example, water, which is interposed between the mask and the photoresist in wet lithography, may penetrate the photoresist and cause the photoresist to swell. As a result, patterns created in the photoresist may become altered.
Therefore, it is desirable to improve the photolithography process.